Busway with resilient connecting means for plural busbars



3 Sheets-Sheet 1 J- W. MEACHAM BUSWAY WITH RESILIENT CONNECTING MEANS FOR PLURAL BUSBARS March 10, 1964 Original Filed Oct. 23 1958 IN V EN TOR.

ATTORNEY JOHN W.MEACHAM 2/42.- W

J. W. MEACHAM 3 Sheets-Sheet 2 INVENTOR.

JOHN W.MEACi-1AM BY ATTORNEY March 10, 1964 BUSWAY WITH RESILIENT CONNECTING MEANS FOR PLURAL BUSBARS Original Filed Oct. 25, 1958 ll. lllllll llel u u n End r n n n u n u I! hu HQHHIIIIJ. z n d u a n H nunuznwunuu m U a n m m u mm i I LWHHHHII a u m m m n n U HI HHHHH \u u 1.. u u i H\ a QLUIIIIIJIIIIFNJIIII ll hr "n D =FI|I1 F- I o n mm mw S on F Mw March 1964 J. w. MEACHAM BUSWAY WITH RESILIENT CONNECTING MEANS FOR PLURAL BUSBARS Original Filed Oct. 23, 1958 5 Sheets-Sheet 3 INVENTOR. JOHN W. MEACH AM Magma W A TTORNEY United States Patent Othce 3,124,642 Patented Mar. 10, 1964 BUSWAY WITH RESILIENT CONNECTING MEANS FOR PLURAL BUSBARS John W. Mcacham, Endwell, N.Y., assignor to General Electric Company, acorporation of New York Original application Oct. 23, 1953, Ser. No. 769,213, now Patent No. 3,015,082, dated Dec. 26, 1961. Divided and this application Apr. 26, 1960, Ser. No. 24,778

11 Claims. (Cl. 174-88) My invention relates to electric power busway systems of the type comprising elongated interconnected housings, or ducts containing a plurality of bus bars and especially to such busway systems of low-ampere-rated capacity. This application is a division of my copending tribution system was due to the fact that no great advantages in the way of ease and low cost of installation were provided by such prior art busway.

It is a general object of my invention to provide an electric power busway of the low-ampere-rated type which is of low cost to manufacture and extremely easy to install, light in weight, and readily adapted to the requirements of any type of industrial or commercial building without the necessity of providing special lengths or fittings.

It is a particular objectjoi the invention to provide an electric power busway system comprising prefabricated sections which may be readily interconnected with ends of corresponding sections Without the necessity of making individual connections of each of the plurality of bars to each corresponding bar of the next section.

It is also an object of my invention to provide a bus- 7 way system of this type including a busway section which can be readily adjusted to any desired length, which nevertheless has rigidity equal to or greater than that of an ordinary non-adjustable length of busway, and which also has an electrical resistance at least as low as a normal non-adjustable straight length.

In accordance with the invention, a busway system is provided including elongated housing sections of generally rectangular cross-section each containing a plurality of elongated parallel bus bars of generally straplike cross-section. The bus bars are arranged in edge-toedge generally coplanar relation throughouttheir major intermediate portions to provide high mechanical resistance to short-circuit stresses, and have longitudinally spaced localized intermediate portions twisted at 90-degrees to the general plane of the intermediate portions, to provide readily usable plug-in contact portions. The

'bus bars of each section have their end portions also dis-J posed in edge-to-edge generally coplanar relation, in a plane generally parallel to the Wide dimension of the housing. End portions of the bus bars are resiliently sup-v ported with relation to the housing and individually movable, and connecting means are provided whereby all ofa plurality of overlapping bus bar ends may be clamped together simultaneously in a single operation, thereby greatly facilitating and simplifying the installation of such busway. I

In accordance with a related aspectof the invention, an adjustable length busway section is provided having a central portion and two adjustable end portions, each ad 2. justable with respect to the center portion, whereby the overall length of the section may be easily varied.

Other advantages of theinvention will become apparent from the following detailed description and the particular extent of the invention will be pointed out in the appended claims.

In the drawings,

FIGURE 1 is a top plan view of a portion of a busway system including two interconnected busway sections, portions thereof being broken away;

FIGURE 2 is a side elevation view of the distribution apparatus of FIGURE 1;

FIGURE 3 is a sectional view as on the line 3-3 of FIGURE 2, the parts being shown in connected condition but prior to tightening of the electrical joint clamping member;

FIGURE 4 is a fragmentary elevation view of the end portions of two busway sections constructed in accordance with the invention and shown being brought togetherpreliininary to joining;

FIGURE 5 is a view similar to FIGURE 4 showing the busway sections in completely connected condition;

FIGURE 6 is a perspective view of an adjustable length busway section constructed in accordance with the invention;

FIGURE 7 is a top plan view of the adjustable length section of FIGURE 6, an intermediate portion thereof being broken away;

FIGURE 8 is a side elevation view of the apparatus of FIGURE 7;

FiGURE 9 is a fragmentary sectional view on enlarged scale of portions of the adjustable length busway section of FlGURE 6;

FIGURE 10 is 'a sectional view of the adjustable length section taken on the line 1010 of FIGURE 7;

FIGURE 11 is a fragmentary sectional view taken generally on the line l111 of FIGURE 8.

In the drawings, the invention is shown as incorporated in a busway system which comprises basic sections of predetermined or fixed length having joint means at each end for connecting each such section to another similar section, and special sections which are adjustable in length. The following. description will refer to the major features of the busway system in the following order: (1) the construction of the basic fixed length section, (2) the joint construction, and '(3) the adjustable length section construction. It will be understood, of course, that while straight sections only are shown for the sake of simplicity, sections of generally similar construction are contemplated to serve as fittings such as fiatwise and edgewise elbows, tees, crosses, junction boxes, end boxes, etc.

1. Basic Fixed Length Section In FIGURES l and 2 are shown a portion of a plug-in busway system incorporating the invention and comprising two fixed-length sections 10 and '11, said sections meeting at the line 12. Each busway section 10 and 11 comprises an elongated generally rectangular metallic housing orenclosure 14 comprising generally channehshaped top and bottom members 13, 13'. Each of the members 13,

13' has outwardly directed flanges 15, which are inter mediate portions. The bus bars are supported at portions 18 by means of a pair of insulating members 19 of sheet insulating material such as vulcanized fiber notched to fit around the bus bars at the twisted portions 18 to prevent substantially all movement of the bus bars with respect to the side walls of the enclosure 14. For the purpose of taking power from the bus bars 16 through the openings in insulating members 25 and 25', there is provided a power take-oh plug-in device such, for example, as shown at 32 of FIGURE 2.

2. Joint Construction The joint construction is detailed in FIGURES 3, 4, and 5. For the purpose of exposing the general contact area adjacent the ends of the bus bars, each busway section 10, 11 has its top and bottom covers 13, 13 offset longitudinally relative to each other. The bus bars 16 are of greater length than either of the busway enclosure covers 13, 13', so that they project at each end into the exposed portions of the housing. At each such end, the bus bars are supported from the enclosure cover portion which projects further at that particular end. For example, at the end of the busway section 1% shown at the left-hand side of FIGURE 1, which will be referred to as the stationary contact end of the busway section for convenience, the bus bars 16 are supported on a unitary insulating block 21 which extends from side to side of the bottom enclosure cover 13 and which is rigidly attached thereto by suitable means, such as by screws or rivets 20. At the other end of the section 10, each of the bus bars 16 has a separate insulating block 44 attached to the end thereof such as by screws 48, as shown in FIGURE 4. A generally C-shaped clamping member 49 of sheet steel extends across all of the sideby-side blocks 44 under and within the interior of the cover 13. The clamping member 49 has a plurality of tangs 50 lanced out of the back wall thereof which serve to position a plurality of compression springs 51 extending into recesses 52 in each of the insulators 44. The compression springs 51 normally urge the ends of the bus bars 16 outwardly away from the cover 13 and away from clamp member 49, as indicated in the upper portion of FIGURE 4, which shows the overlapped ends of two sections just prior to joining. The housing cover member 13 has a portion of the side flanges thereof cut away as at 53 to permit the side flanges 54 of the clamping member 49 to project outwardly of the housing. The projecting portions 54 of the clamp member 49 are provided with holes through which clamping bolts 55 are inserted for clamping the channel-shaped clamp member toward and against the corresponding flange portion 15 of the opposite housing member 13.

When two sections are assembled, referring to FIG- URES 4 and 5, they are brought into overlapping relation with the ends of the bus bars 16 overlapping. Each of the housing cover sections 13 and 13' is provided with a joint splice plate 56 which is suitably rigidly attached thereto at the end portion by suitable means such as by welding and which projects beyond the end of the corresponding housing cover on which it is mounted. When two sections are to be joined, they are brought together in partially overlapping relation as indicated in FIGURE 4, with the edges 13a in mutually abutting relation. The main housing portions of the duct sections are, therefore, brought into end-to-end directly abutting relation, with the splice plates 56 of the top and bottom cover members overlapping the edges of corresponding cover portions. A pair of bolts 57 (see FIGURE 1) are then inserted at each side of the busway assembly, threadably engaging nuts carried by the underside of the flanges 15 and held in place in alignment with the bolt holes by suitable means such as by welding. The splice plates 56 and bolts 57 serve to physically anchor the two ends of the busway sections together.

Following the mechanical connection of the housing 4 sections together by bolts 57, the bus bars 16 are clamped together by means of the bolts 55 which engage co1re= sponding nuts held in the housing member of the opposite section. The bolts 55 serve to draw the yoke or clamp member 49 toward and against the flanges of the bottom housing section, compressing the springs 51 and urging the end portions of bus bars 16 into positive engagement with the corresponding end portions of the bus bar 16 of the adjacent section. Thus, all the bars are clamped into tight electrical engagement by tightening only two clamping screws, one at each side of the as se'rnblyi v F 3. Adjustable Length Sectior't In accordance with the invention, a busway section is also provided which, through the use of a joint construction similar to that described above, can be adjusted as to length throughout a substantial distance, so that it is unnecessary to measure exactly the length of busway needed for a particular installation.

In accordance with this aspect of the invention, and referring particularly to FIGURES 6ll, an adjustable length busway section 61) is provided comprising three relatively movable sections including a main central section 61 which, for convenience, will be referred to as the stationary section, and two movable end sections 62 and 63. The central section 61 includes top and bottom housing cover members 64 and 65 respectively.

The bottom housing member 65 of the central section has two longitudinal spaced insulating blocks 86) (see FIGURES 9 and 10) mounted thereon and each extending transversely of the housing. Each of the blocks 80 has a number of channel-like recesses 80a serving to support and guide portions of the bus bars of each of the end sections 62, 63, respectively. Extending be tween the insulators 8t) and overlying portions of the bus bars 75, are a plurality of short bridging bus bar sections 66, each having an enlarged generally rectangular insulating tube 67 surrounding its intermediate portion. The bus bars 66 each have a small block of insulating material 68 rigidly attached to the ends thereof, the insulating blocks 68 at each end of the bus bars 66 are transversely aligned above the insulators and are each retained in position by a clam-ping member 70 which has outwardly extending flanges attached to the corresponding flange portions of the bottom housing member 65 by suitable means such as by screws 71. The clamping member 7t} is similar to the clamping member 49 of the joint portion shown in FIGURE 3 and has a plurality of depending tangs 72 struck from the back wall thereof to assist in postioning a plurality of compression springs 73 which bias the insulating blocks 68 away from the clamp member '76 and toward the block 841 to provide contact pressure.

The central section 61 telescopically receives the housing portions 74 of the end sections 62 and 63. The construction and operation of each of these sliding end portions are substantially identical except for their bus bar outer termination provisions as will be described, and, therefore, the construction and operation of the end portion 63 only will be described in detail. The end section 63 includes a generally rectangular metallic housing portion 74 which is telescopically and slidably received in the main housing between the housing members 64 and 65. and an outer or joint portion 74' generally similar to that shown at the bottom portion of FIGURES 4 and 5. The end portion 74' has bus bar ends 75 mounted on a common stationary insulating block 75' extending transversely of the busway housing and rigidly attached thereto such as by rivets, and also has a joint splice plate 56 rigidly attached thereto such as by welding. The bus bars 75 are also rigidly supported adjacent the inner end of the housing 74- on a similar insulating block 76 extending transversely of the housing. The inner ends of the bus bars 75 are slidably guided in channels 800 of the insulators 80 and extend beyond the insulators 80 under the bridging bus bars 66 within the insulating tubes 67 asdescribed above.

The movable end portion. 63 has a spring catch member 77 (see FIGURE 11) carried by the inner surface of one sidewall portion and extending through an opening 77a therein. The top cover member 64 of the central section is provided with an opening 78 into which the catch 77 drops when the end section '63 is-pulled outwardly a predetermined amount, to limit such outward movement, Subsequent inward movement of the end section causes the catch 77 to be cammed inwardly again by the edge of the openingv 78.

The construction of the slidable end section 62 is similar to that of the end section 63, with the exception that the bus bar outer termination construction is similar to that shown in the upper portion of FIGURE 4, carrying the movablecontact endsof the bus bar.

The adjustable length section of this invention combines a. wide range of adjustment with a high amount of mechanical strength or rigidity in the fully extended position. If only two relatively movable sections were used, the amount of telescoping engagement would have to be twice that of either end section of the present invention; making it more difficult to provide rigidity to the assemblywithout further increasing its over-all length. In addition, this general construction has the advantage that the central section may be installed at a predetermined hanger location, and the outer ends thereof adjusted to provide a desired over-all length such as to bridge a fixed gap.

While I have described preferred embodiments of the invention, it will be apparent that many modifications thereof may be made, and I therefore intend, by the appended claims, to cover all such modifications as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. An electric power busway system comprising: a plurality of interconnected lengths of busway, each of said busway lengths including an enclosure of generally rec-- tangular cross-section and a plurality of electric power bus bars supported in substantially a common plane in edge-to-edge insulated relation therein, the bus bars in one length overlapping the ends of respective bus bars in the next adjacent length; means for securing the enclosures of adjacent busway lengths to each other; an insulating number, said bus bars having the overlapping ends thereof adjacent one side wall of said enclosure rigidly supported onsaid insulating member and aligned transversely of the direction of overlap, a separate insulating block attached toeach of the overlapping bus bar ends adjacent the opposite sidewall ofsaid enclosure, said insulating blocks each having a relatively deep recess therein in' the side opposite from said bus bars, a compression spring in each of the recesses of said insulating blocks urging each of said blocks away from said opposite wall of said enclosure, said insulating blocks being individually movable and dimensioned transversely of said enclosure so that said blocks extend in closely spaced side-by-side relation substantially completely from side to side of said enclosure.

2. Anelegtric power busway system comprising: a plurality of interconnected lengths of busway, each of said busway lengths including an enclosure of generally rectangular cross-section and .a plurality of electric power bus bars supported in substantially a common plane in edgeto-edge insulated relation therein, the bus bars in one length overlapping the ends of respective bus bars in the next adjacent length; means for securing the enclosures of adjacent busway lengths to each other; and means 'for interengaging the said overlapping ends of said bus bars including a stationary insulating member rigidly secured between one side of said overlapping bus bar ends and a first wall of the immediately adjacent enclosure, a plurality of blocks of insulating material each fastened to busway lengths including an enclosure of generally rec-- respective bus bars on the other side of said overlapping bus bar ends, and a plurality of compression springs each mounted between a respective one of said insulating blocks and an enclosure wall opposite from said first wall, thereby to urge respectively overlapping pairs of said bus bars into firm mutual engagement.

3. An electric power busway system comprising: aplurality of interconnected lengths of busway, each of said busway lengths including an enclosure of generally rectangular cross-section and a plurality of electric power bus bars supported in substantially a common plane in edge-to-edge insulated relation therein, the bus bars in one length overlappingthe ends of respective bus bars in the next adjacent length; means for securing the enclosures of adjacent busway lengths to each other; an insulating spacer rigidly secured to an enclosure wall adjacent one side of said overlapping ends; and a plurality of insulating blocks each independently and resiliently biased away from an enclosure wall adjacent the opposite side of said overlapping bus bar ends and compressing said overlapping bus bar ends against said insulating spacer.

4. An electric power busway system comprising: a plurality of interconnected lengths of busway, each of said tangular cross-section and a plurality of electric power bus bars supported in substantially a common plane in edge-to-edge insulated relation therein, the bus bars in one length overlapping the ends of respective bus bars in the next adjacent length; means for securing the enclosures of adjacent busway lengths to each other; and means for interengaging the said overlapping ends of said bus bars including a stationary insulating member rigidly secured between one side of said overlapping bus bars and a first wall of the immediately adjacent enclosure, a plurality of blocks of insulating material each fastened to a respective overlapping bus bar end adjacent a second wall.

of the immediately adjacent enclosure opposite saidfirst.

wall, a clamping member extending across said insulating blocks adjacent said second enclosure wall, and a plurality of compress-ion springs each mounted between a respective one of said insulating blocks and said clamping member, and means for drawing said clamping member toward said stationary insulating member thereby to compress said springs and clamp said overlapping bus bars between said insulating spacer and respective ones of said insulating blocks.

5. An electric power busway section comprising an elongated enclosure of generally rectangular cross-section having oppositely positioned walls, a pluralityv of electric power bus bars supported in substantially a common plane in edge-to-edge insulated relation in said enclsoure between said walls, means supporting the ends of said bus bars in insulated fixed relation with one of said walls at one end of said enclosure, means supporting the other ends of said bus bars in insulated resiliently movable relation with the other of said walls at the other end of said enclosure, saidwalls being offset longitudinally to expose said supported ends of said bus bars at both ends of said section, and clamping means for clamping at least one end of said section to another similar busway section.

6. An electric power busway section, comprising an having top and bottom walls, a plurality of electric power bus bars supported in substantially a common plane in edge-to-edgeinsulated relation in said enclosure between said walls, means supporting the ends of said bus bars in insulated relation on said bottom wall at one end of said enclosure, separate resilient means between the end of each of said bus bars and said top wall of said enclosure at the other end of said section whereby each of said ends of said bus bars at said other end of said section are individually resiliently movable toward and away from said top wall, means insulating said ends of said bus bars from said top wall, and clamping means for clamping said busway section to another similar busway section in end-to-end relation,

7. An electric power busway section comprising an elongated enclosure of generally rectangular cross-section, a plurlity of electric power bus bars supported in sub stantially a common plane in edge-to-edge insulated relation in said enclosure, insulating means supporting ends of said bus bars at one end of said enclosure, a separate block of insulating material associated with each of said bus bar ends at the other end of said enclosure with said last-named ends being transversely aligned of said housing, and a compression spring between each of said insulating blocks and a wall of said housing opposite from said first wall.

9 8. An electric power busway system comprising an elongated enclosure of generally rectangular cross-section, a plurality of electric power bus bars supported in insulated edge-to-edge relation in substantially a common plane in said enclousre, an insulating member, said bus bars having the ends thereof at one end of said enclosure rigidly supported on said insulating member and transversley aligned of said enclosure, a separate insulating block attached to each of the bus bar ends at the other end of said enclosure, said insulating blocks each having a relatively deep recess therein in the wall opposite from said bus bars and adjacent a wall of said enclosure, a compression spring in each of said recesses of said insulating blocks urging each of said blocks away from said wall of said enclosure, said insulating blocks being individually movable and dimensioned tranversely of said enclosure so that said blocks extend in closely-spaced sideby-side relation substantially completely from side to side of said enclosure.

9. An electric power busway system as set forth in claim 8 wherein said busway section also includes a generally C-shaped clamping yoke extending across said movable insulators and between said springs, said clamping member having outwardly extending flange portions and said enclosure including outwardly extending flange portions opposed to said clamp flange portions, and means for drawing said clamp toward and against said enclosure flanges to compress said springs against said insulating blocks.

10. An adjustable length busway section comprising a center section having an elongated enclosure of generally rectangular cross-section having opposed top and bottom walls, a pair of spaced insulating supports mounted on said bottom wall, each of said insulating supports having a plurality of side-by-side channel portions, a pair of adjustable end sections each including a generally rectangular enclosure portion telescopically engaged with said enclosure of said center section, a plurality of side-by-side bus bars supported in insulated relation in each of said end sections and including portions extending into and slidably supported in said channels of said insulators, a plurality of bridging bus bars extending from one insulating support to the other and overlapping portions of said bus bars of said end sections, a separate block of insulating material attached to each of said bridging bus bars at the end thereof above said stationary insulating support, said center housing including flange portions extending transversely outwardly from the side portions thereof adjacent said insulator supports, clamping means extending transversely of said center section from side to side thereof across said aligned ends of said bus bars, compression spring means between said clamping means and said insulators for clamping said bridging bus bars to said adjustable end section bus bars, and means for clamping said clamping means to said flanges.

11. An adjustable length power busway section comprising a main center section having a 'pair of confronting generally channel-shaped housing members having side portions thereof terminating in outwardly directed flange portions,'means connecting said flange portions of said housing members together to provide a unitary elongated enclosure of generally rectangular cross-section, a pair of longitudinally displaced insulator supports mounted on the bottom wall of said enclosure, a plurality of bridging busbars extending between said insulator supports, an adjustable end section at each end of said main section and each including a generally rectangular enclosure portion extending in telescopically engaged relation with respect to said main housing portion, a plurality of bus bars supported in side-by-side insulated relation in each of said adjustable end sections and including portions extending into said center section and over at least one of said insulating supports in overlapping relation to portions of said bridging bus bars, a generally C-shaped clamping yoke extending transversely of said center section and having flange portions opposed to said flange portions of said bottom housing section, a plurality of side-by-side insulating blocks supported between the inner surface of said yoke member and the overlapping portions of said bus bars, resilient spring means between said yoke portion and each of said insulator members for pressing said overlapping bus bar portions together, fastening means for connecting said flange portions of said clamping member to said flange portions of said bottom housing member to compress all of said overlapping bus bar portions together and against one insulator assembly, and means for limiting the movement of each of said adjustable end sections outwardly of said main central section.

References Cited in the file of this patent UNITED STATES PATENTS 2,009,376 Frank July 23, 1935 2,287,502 Togesen et al. June 23, 1942 2,350,601 Frank et a1. June 6, 1944 2,372,267 Frank et a1. Mar. 27, 1945 2,749,385 Adam June 5, 1956 2,903,503 Carlson et al Sept. 8, 1959 2,906,811 Fisher Sept. 29, 1959 2,945,137 Farnsworth July 12, 1960 3,004,097 Johnston et al Oct. 10, 1961 FOREIGN PATENTS 569,263 Canada Jan. 20, 1959 814,492 Great Britain June 3, 1959 1,200,923 France July 6, 1959 

3. AN ELECTRIC POWER BUSWAY SYSTEM COMPRISING: A PLURALITY OF INTERCONNECTED LENGTHS OF BUSWAY, EACH OF SAID BUSWAY LENGTHS INCLUDING AN ENCLOSURE OF GENERALLY RECTANGULAR CROSS-SECTION AND A PLURALITY OF ELECTRIC POWER BUS BARS SUPPORTED IN SUBSTANTIALLY A COMMON PLANE IN EDGE-TO-EDGE INSULATED RELATION THEREIN, THE BUS BARS IN ONE LENGTH OVERLAPPING THE ENDS OF RESPECTIVE BUS BARS IN THE NEXT ADJACENT LENGTH; MEANS FOR SECURING THE ENCLOSURES OF ADJACENT BUSWAY LENGTHS TO EACH OTHER; AN INSULATING SPACER RIGIDLY SECURED TO AN ENCLOSURE WALL ADJACENT ONE SIDE OF SAID OVERLAPPING ENDS; AND A PLURALITY OF INSULATING BLOCKS EACH INDEPENDENTLY AND RESILIENTLY BIASED AWAY FROM AN ENCLOSURE WALL ADJACENT THE OPPOSITE SIDE OF SAID OVERLAPPING BUS BAR ENDS AND COMPRESSING SAID OVERLAPPING BUS BAR ENDS AGAINST SAID INSULATING SPACER. 